Electrocatalytical Properties of a Potassium Hexacyanoferrate (II) Modified Polypyrrole Electrode. Application to Vitamin C Determination

ABSTRACT

An electrocatalytic detection on a potassium hexacyanoferrate (II) modified polypyrrole electrode has been studied. The pyrrole electropolymerization was carried out on a Pt disk of 3 mm diameter, using constant potential chronoamperometry in the presence of the modifier. The electrochemical control of the electropolymerization and modification permit us to know the polymerisation charge, Q_p, as well as the number of moles of K₄Fe (CN)₆ incorporated into the polymer at its generation step using Faraday's Law. Finally a determination method for vitamin C (ascorbic acid) using scan and differential pulse voltammetry was developed. This method was applied to determination of vitamin C in several samples, such as tablets and orange drinks, using the standard addition method.

Keywords::

• Electrocatalysis
• potassium hexacyanoferrate (II) modified polypyrrole electrode
• vitamin C determination